Optical connector for sterile applications

ABSTRACT

An optical connector system for reversible optical connection between two optical fibers ( 102, 104 ) with their end parts inside respective ferrules. A receptacle arrangement has a receiving body ( 105 ) for receiving at least one of the ferrules ( 103 ). An optical element ( 106 ) of the receptacle arrangement serves to provide optical connection between the two optical fibers in a connected state of the optical connector system, and at the same time, the optical element ( 106 ) serves as a sterility barrier between the two optical fibers. The optical element ( 106 ) can be an optical waveguide, e.g. a piece of optical fiber similar to the two optical fibers ( 102, 104 ), and arranged within the receiving body ( 105 ). Alternatively, the optical element may be a thin flexible membrane ( 207, 307 ) which is optically transparent. As a further alternative, the optical element may be a sterilizing fluid ( 409 ) arranged inside a container that can be punctured upon insertion of one of the ferrules ( 401, 403 ) into the container ( 408 ), to allow an optical fiber end to be sterilized by the fluid ( 409 ) prior to entering into the connected state. In a further embodiment, an optical lens ( 312 ) is used to project light from one fiber end through a membrane ( 307 ) to the opposite fiber end.

FIELD OF THE INVENTION

The present invention relates to the field of connectors for opticalfibers. More specifically, this invention relates to optical connectionsallowing connection and disconnection in a sterile zone.

BACKGROUND OF THE INVENTION

In minimally invasive medical interventions needles, guide wires,sheaths and catheters are inserted in the patient in order to find andmeasure, on the one hand, the relevant anatomy of the patient and treator place a stent (for example) on the other hand. Clearly, the part ofthe devices inserted into the patient either must be sterile at alltimes or should only be contaminated with fluids and tissue from thepatient itself. When a needle, guide wire or catheter is armed with asensor or actuator, some connection (for example electrical wire oroptical fiber) must be made to transmit the information or power to orfrom a controller or interrogator placed in the non-sterile zone, awayfrom the patient. Somewhere along the transmission line, the sterilezone meets the non-sterile zone. This setup requires proper managementof sterility.

The use of optical interrogation techniques in minimally invasivemedical interventions requires that, on the one hand, the optical sensoris inserted in the patient and must be sterile and, on the other hand,that the optical waveguide that transmits the optical information isplugged into a mating sleeve of a patch cord, controller or interrogatorplaced in the non-sterile zone, away from the patient. Upon making theoptical connection, the sterile proximal end of the optical sensor comesin contact with the non-sterile patch cord, controller or interrogatorthereby also becoming non-sterile. During a medical procedure asterility problem may arise in case the optical waveguide needs to bedisconnected and the (now non-sterile) proximal end of the medicaldevice containing the optical sensor needs to enter the sterile zone orwhen devices have to slide over the medical device containing theoptical sensor. The latter is for example the case when a so-calledback-loadable guide wire armed with optical shape sensing (OSS) is used.In essence, whenever the proximal end of a guide wire becomesnon-sterile, the next device (a catheter or stent) that slides over itwill transport the contamination into the body of the patient.

U.S. Pat. No. 5,949,929 discloses an interventional medical devicehaving a rotatable optical fiber, an assembly having a conduit forconveying a light beam to the rotatable fiber as well as a rotor and afixed housing, and a coupling. The coupling includes a rotatable portionattachable to a proximal end of the rotatable fiber and to the rotor soas to permit the rotatable fiber to rotate continuously with the rotorwhile the rotatable fiber remains in axial alignment with the lightbeam. The proximal end of the rotatable portion of the coupling has aV-shaped coupling surface that complements a distal end surface of therotor. In some embodiments, a GRIN (gradient index of refraction) lensis arranged between the stationary optical fiber and the rotatableoptical fiber which reduces the need for precise alignment of theoptical fibers.

SUMMARY OF THE INVENTION

It would be advantageous to provide an optical connector system that isnon-sterile at one end, but remains sterile at the other end. E.g. toallow medical back-loading procedures, e.g. so as to allow optical shapesensing to be applied in medical back-loading procedures. Further, itwould be advantageous that the optical connector provides a highinsensitivity to rotation, thus allowing application for rotationsensitive optical fibers. Still further, the connector system should bepossible to manufacture in miniature versions.

In a first aspect, the invention provides an optical connector systemarranged to provide a reversible optical connection between associatedfirst and second optical fibers, comprising:

-   -   a first ferrule with an outer body and arranged for having an        end portion of the associated first optical fiber arranged        inside,    -   a second ferrule with an outer body and arranged for having an        end portion of the associated second optical fiber arranged        inside, and    -   a receptacle arrangement comprising a receiving body, wherein        the receptacle arrangement is arranged to receive an end part of        the outer body of at least the second ferrule, wherein the        receptacle arrangement further comprises an optical element        serving to provide optical connection between the associated        first and second optical fibers in a connected state of the        optical connector system, and wherein the optical element serves        as a sterility barrier between the associated first and second        optical fibers.

Such optical connector system is advantageous since it allows e.g. thefirst ferrule to be non-sterile, while the second ferrule is sterile,since the optical element serves as a sterility barrier, e.g. forconnecting a sterile guidewire and a non-sterile patch cord. Still, theconnector system can be manufactured in versions that allows medicalback-loading procedures. The optical connector system is furtheradvantageous since it is well suited for miniature applications, due tothe low complexity and the possibility of implementation with few singlecomponents.

E.g. the optical connector system may be used to connect a guidewirethat may be used for optical tissue examination and/or optical shapesensing (OSS). The first and second optical fibers may be single ormulti-core optical fibers. It is to be understood that the opticalelement serves to provide optical connection between the first andsecond optical fibers. Preferably, the optical element, e.g. an opticalwaveguide, is selected to match the type of the first and second opticalfibers, so as to provide a low optical low loss in the connected state,and so as to provide optical connection, in the connected state, betweeneach single fiber core of the first and second optical fibers, in casethese comprise multiple fiber cores.

Furthermore it is advantageous to make the connector system allow forrotational alignment of the first and second optical fibers. A notlimited list of examples of optical fibers where such a connector systemis advantageous are: 1) optical fibers with off-axis core(s), such asmulti-core fibers, 2) photonic crystal fibers which do not have acircular symmetric core-structure, 3) optical fibers where the core hasdifferent polarization dependent propagation properties, such as inpolarization maintaining fibers, and 4) optical fibers with an anglepolished end facet, as is typical for angled physical contact (APC)connections.

By ‘ferrule’ is understood an element serving to at least partlyencapsule the end of the optical fiber. Thus, e.g. a guide-wire orsimilar is understood to be a ferrule. The ferrule may in general beformed by various materials, e.g. polymers, metals or combinationsthereof.

In the following, a number of embodiments or optional features will bedefined.

The receptacle arrangement may be arranged to receive the end part ofthe outer body of the first ferrule in one end, and to receive an endpart of the outer body of the second ferrule in its opposite end, andwherein the optical element comprises an optical waveguide arrangedwithin the receiving body. Especially, the optical waveguide may besimilar to the first and second optical fibers, e.g. formed by the samematerial as one of or both of the first and second optical fibers or atleast have similar optical interfaces. The waveguide may be formedintegrally with the receiving body, e.g. positioned inside the receivingbody and fastened to the receiving body. The optical waveguide serves asa sterility barrier, since it can be sterile in one end whilenon-sterile in its opposite end.

The optical element may comprise an optically transparent membrane.Especially, the optically transparent membrane may be flexible, i.e. itmay be formed by a flexible, and arranged to partially encapsulate theassociated first or second optical fiber (or at least partiallyencapsulate the first or second ferrule) in the connected state. Theoptical connector system may further comprise a plug arranged to receivethe first ferrule, and wherein the plug is arranged to fit inside thereceiving body. Especially, the plug may be arranged to receive thefirst ferrule in one end, and wherein the optically transparent membraneis positioned at an opposite end of the plug. Especially, the opticalconnector system may comprise a first plug arranged to receive the firstferrule, wherein the first plug is arranged to fit inside a second plug,and wherein the second plug is shaped to fit inside the receiving body.E.g. the optically transparent membrane is positioned to cover one endof the second plug.

The sterility barrier may strongly absorb or strongly reflect light at awavelength different than the usual operation wavelength (where itshould be highly transparent). Strong absorption can be delivered by adye while strong reflection can be achieved by writing a fiber Bragggrating into the barrier with the proper periodicity. By sending a pulseof light with a wavelength in the absorption/reflection band and bydetecting how much of the pulse is being reflected one can detect if thesterility barrier is present in the optical path or not.

The optical connector system may comprise a second optical elementarranged to project light from one of the associated first and secondoptical fibers via the optically transparent membrane to the oppositeone of the associated first and second optical fiber. Especially, thesecond optical element may comprise an optical lens, or a combination ofoptical lenses, or mirrors, positioned between the first optical fiberand the optically transparent membrane. Such embodiments allows opticalconnection without any structural contact between the receptablearrangement and the first ferrule.

The receptable arrangement may comprise a container with a sterilizingfluid. Said container may be arranged to receive the first ferrule andbe arranged to puncture upon insertion of the first ferrule into thecontainer, so as to allow sterilization of at least an end part of theassociated first optical fiber by means of contact with the sterilizingfluid, upon insertion of the first ferrule insertion into the container.The container may be formed as a (replacable) cartridge. Especially, asponge element may be comprised within the container, wherein at least apart of said sterilizing fluid is soaked into the sponge element. Thesponge element may be arranged to mechanically clean at least part ofthe associated first optical fiber during insertion of the first ferruleinto the container, prior to entering into the connected state. Morespecifically, the sponge element may have a prefabricated hole arrangedfor the first ferrule to penetrate through, so as to allow theassociated first optical fiber to provide optical connection with theassociated second optical fiber, in the connected state.

It may be preferred that the receiving body is arranged to surround endparts of outer bodies of both of the first and second ferrules in aconnected state of the optical connector system. Hereby, the connectionbetween the first and second ferrules can be encapsulated or at leastshielded.

The first and second ferrules may have outer bodies with non-circularcross sections of at least their end parts, and wherein the receptaclearrangement forms a receiving opening arranged to receive the end partsof the outer bodies of the first and second ferrules from oppositesides, and wherein a cross-sectional shape of a receiving opening atleast partly matches the non-circular shape of the end parts of theouter bodies of the first and second ferrules, so as to provide arotational locking mechanism serving to restrict relative rotationbetween the first and second ferrules. Such embodiment provides a highrotational stablility, and is thus especially suited for first andsecond optical fibers with multile fiber core. By ‘non-circular crosssection of at least an end part’ is to be understood an end part whichdoes not have a circular cross section around its entire periphery. Suchtotal circular cross section would not be able to provide theadvantageous rotational locking or inhibiting effect of the first andsecond ferrules by engagement with the receptacle arrangement. However,the cross section of the end part of the first and second ferrules maybe partly circular, i.e. circular along a part of its periphery, whilenon-circular, e.g. flat, on the remaining part of its periphery.

The associated first and second optical fibers may be mountedrotationally fixed to the respective first and second ferrule, so as toensure that the first and second optical fibers are effectivelyrotationally locked by the optical connector system.

The receiving opening may have different cross-sectional shapes in eachend, being shaped to fit respective first and second ferrule outerbodies with different cross-sectional shapes. In other embodiments thefirst and second ferrules have similar outer body cross-sectionalshapes, thus being shaped to fit a receiving opening with similarcross-sectional shape in both ends.

The system may comprise a separate element serving to fix or lock thefirst and second ferrules together in a longitudinal direction, so as toprovide a stable optical connection between the first and second opticalfibers. Such separate element may be a polymeric element, a metallicelement, or the longitudinal fixing or locking it may be provided by ashrink tube around the first and second ferrules.

Preferably, the optical connector system is arranged for reversiblyconnection such that a user can connect and disconnect the first andsecond optical fibers by means of the optical connection system, withoutthe need for any tool.

The first and second associated optical fibers may be multi-core opticalfibers. An example of a specific type of multi-core optical fiber is anoptical fiber comprising four single mode optical fiber cores, e.g. onecentral fiber core, and three additional fiber cores helically arrangedaround the central fiber core.

In a second aspect, the invention provides an optical system comprisingfirst and second optical fibers, and an optical connector systemaccording to the first aspect.

In a third aspect, the invention provides a medical system comprising aninterventional medical device optically connected to an optical systemaccording to the second aspect.

In a fourth aspect, the invention provides a method for reversiblyconnecting first and second optical fibers, the method comprising:

-   -   providing a first ferrule with an outer body and an end portion        of the first optical fiber arranged inside,    -   providing a second ferrule with an outer body and an end portion        of the second optical fiber arranged inside, and    -   providing a receptacle arrangement with an optical element, and    -   inserting at least an end part of the outer body of the first        ferrule into a receptacle arrangement comprising an optical        element, so as to provide optical connection between the first        and second optical fibers via the optical element, wherein the        optical element serves as a sterility barrier between the first        and second optical fibers.

It is appreciated that the same advantages and embodiments of the firstaspect apply as well for the second, third, and fourth aspects. Ingeneral the first, second, third, and fourth aspects may be combined andcoupled in any way possible within the scope of the invention. These andother aspects, features and/or advantages of the invention will beapparent from and elucidated with reference to the embodiments describedhereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will be described, by way of example only,with reference to the drawings, in which

FIG. 1 shows a sketch of an embodiment with an optical waveguide actingas sterility barrier,

FIG. 2 shows a sketch of an embodiment with a thin flexible membraneacting as sterility barrier,

FIG. 3 shows a sketch of an embodiment with a combination of a membraneand an optical lens,

FIG. 4 shows a sketch of an embodiment with a cartridge containing asterilizing fluid,

FIG. 5 shows a sketch of an embodiment with a sterile plug and membrane,

FIG. 6 shows a sketch of an embodiment similar to FIG. 5, but with anadditional plug, and

FIG. 7 illustrates a diagram of steps of a method embodiment.

DESCRIPTION OF EMBODIMENTS

FIG. 1 illustrates a side section view of an optical connector systemembodiment where a receptacle arrangement forms a connecting piece 105,106 for connecting two ferrules 101, 103. To the left a sketch shows thesystem in a disconnected state, and to the right the system is shown ina connected state. First and second ferrules 101, 103 have respectivefirst and second optical fibers 102, 104 arranged therein. The opticalfibers 102, 104 may be multi-core optical fibers, and they reside in thecenter of the ferrules 101, 103. Ends of the ferrules 101, 103 areinserted from opposite ends of a receiving body 105 forming part of areceptacle arrangement. An optical element 106 in the form of a shortoptical waveguide, e.g. multi-core waveguide, is arranged inside thereceiving body 105. The optical element 106 serves to provide an opticalconnection between the first and second optical fibers 102, 104 in aconnected state, namely by forming an optical transmission path, ormultiple transmission paths, between the end of the first optical fiber102 and the end of the second optical fiber 104, in the connected state.The optical element 106 may be mounted in a fixed manner inside thereceiving body 105, and the optical element 106 serves as a sterilitybarrier between the first and second optical fibers 102, 104, since itprevents the first and second optical fibers 102, 104 from entering intocontact. Thus, the second optical fiber 104 and the second ferrule 103may continue to be sterile even after optical connection to the firstoptical fiber 102, and the first ferrule 101 which are non-sterile.

For a low loss optical connection, it is required to have the modestructure and the geometry of the sterility barrier waveguide 106 assimilar as possible to the optical fibers 102, 104 to be connected. Thefact that the optical element 106 forming the optical connection is awaveguide or optical fiber itself ensures that the optical mode does notdiverge on propagating from the non-sterile optial fiber 102 to thesterile optical fiber 104. Especially in case the first and secondoptical fibers 102, 104 are multi-core optical fibers, a rotationallocking arrangement may be provided so as to prevent relative rotationbetween the first and second ferrules 101, 103, and the optical element106.

The optical element 106 may be made sterilizable such that it can bere-used for multiple medical interventions. Preferably, the opticalelement 106 may be made an integral part of the receiving body 105, thatforms a hermetic seal and is sterilized with the receiving body 105.

FIG. 2 shows a side section view of an embodiment with an opticalelement in the form of a thin membrane 207 positioned between the twooptical fibers 202, 204 to act as a sterility barrier. To the left theembodiment is shown in a disconnected state, i.e. with the ferrules 201,203 outside the receiving body 205. The thin and flexible membrane 207covers one end of the receiving body 205. To the right, the connectedstate is shown, where the ferrules 201, 203 have been inserted into thereceiving body 205 from opposite sides, and where the flexible membrane207 now partly encapsulates the first ferrule 201, and the membrane 207serves to prevent direct contact between the first and second opticalfibers 202, 204.

The membrane 207 could be either sterilizable or sterile and disposableafter each intervention. The membrane 207 is preferably opticallysufficiently transparent, at least for the intended wavelength range, toallow light to couple from the first optical fiber 202 to the secondoptical fiber 204 through the membrane 207. In contrast to theembodiment in FIG. 1, the membrane 207 itself does not guide the lightin a finite area. The optical mode coming from one optical fiber 202will just diverge as it propagates through the membrane 207. It willtherefore induce some coupling loss at the other optical fiber 204,depending on the thickness of the membrane 207. Assuming that bothoptical fibers 202, 204 have the same propagating mode (or propagatingmodes in e.g. a multicore fiber) with a radius w₀, the powertransmission T as function of a gap distance Δz introduced by themembrane is given by

${T = \frac{1}{1 + \left\lbrack \frac{\Delta \; z\; \lambda}{2\pi \; {nw}_{0}^{2}} \right\rbrack^{2}}},$

where n is the refractive index of the membrane and λ the wavelength ofthe light. See e.g. “Loss Analysis of Sinlge-Mode Fiber Splices”, D.Marcuse, The Bell System Technical Journal, Vol. 56, No. 5, May-June1977, pp. 703-718. For realistic parameters it means that if we want tokeep the insertion loss lower or equal to 1 dB, the membrane thicknessis preferably in the order of a few tens of micrometers or thinner.

Further, in order to minimize the reflections at the interface betweenthe membrane 207 and the optical fibers 202, 204, the refractive indexof the membrane 207 is preferably selected to be as close as possible tothat of the optical fibers 202, 204.

A possible suitable material for the membrane 207 is fluorinatedpolymers to keep both the refractive index low and contamination low.Further suitable materials are polyimide (thin and strong), polyethylene(stretchable), high-density polyethylene (HDPE), Para film(stretchable), latex (stretchable).

In an alternative version of the embodiment of FIG. 2, the membrane 207is either very plastic or elastic, or it may have a tubular or conicalshape, so that it fits around an end of one of the ferrules 201, 203.

FIG. 3 shows side view sketches of an embodiment for connecting firstand second ferrules 301, 303, with respective optical fibers 302, 304arranged inside. Again, the sketch to the left shows a disconnectedstate, while the connected state is shown to the right. A thin opticallytransparent membrane 307 is arranged to cover one end of a receivingbody 305 which is arranged to receive the second ferrule 303 from theopposite end. Apart from the membrane 307, the receptable arrangementcomprises a further optical element (or multiple optical elements),namely an optical lens 312 positioned between the first and secondoptical fiber 302, 304, e.g. acting as a relay lens. Here, it is shownpositioned between the first optical fiber 302 and the membrane 307.This arrangement does not requiree that the two optical fibers 302, 304are as close as possible, but the optical element(s) 312 can project oneoptical interface onto the other allowing for more design freedom of thetransparent membrane 307. The optical element(s) 312 are preferablyplaced at the side of the non-sterile optical fiber 302 so that it doesnot have to be sterile or sterilized.

FIG. 4 shows side view sketches of an embodiment for connecting firstand second ferrules 401, 403, with respective optical fibers 402, 404arranged inside. Again, the sketch to the left shows a disconnectedstate, while the connected state is shown to the right.

This embodiment comprises a container 408, e.g. formed as a cartridge,with sterilizing fluid 409, such as alcohol or some iodine solution, tosterilize the non-sterile optical fiber 402 right before the actualconnection to the second optical fiber 404 is made. The sterilizationcould be done by having a cartridge 408 with sterilizing fluid 409 orgas that will be punctured upon insertion of the non-sterile part, i.e.the first ferrule 401 with the first optical fiber 402 inside.

As seen, both first and second walls of the container 408 have beenperforated by the first ferrule 401 in the connected state. Especially,these walls may be formed by thin elastic materials, that may serve toprevent the fluid 409 from leaking during the penetration of the firstand second walls. In the connected state, at least a film of thesterilization fluid on the end of the first optical fiber 402 acts as acombined optical element between the first and second optical fibers402, 404, i.e. it serves as optical connection, and it acts as asterility barrier between the first and second optical fibers 402, 404.When entering the connected state, the sterilization fluid 409 has actedto sterilize at least the end of the first optical fiber 402.

Inside the cartridge 408, there may be a sponge (not visible) soaked incleaning and sterilizing fluids 409 such as ethanol, or an iodinesolution. The sponge may have a prefabricated puncture or hole orchannel so that the non-sterile ferrule 401 can easily pass to the otherside of the cartridge 408, despite that the hole may be squeezed tight.The latter is beneficial because a direct path between the two sides ofthe cartridge 408 (the sterile and non-sterile zone) is closed. It isalso beneficial because the non-sterile ferrule 401 and fiber 402 isrubbed by the sponge when inserted and hence a mechanical cleaning ofthe ferrule 401 and fiber 402 is achieved.

FIG. 5 shows side view sketches of an embodiment for connecting firstand second ferrules 501, 503, with respective optical fibers 502, 504arranged inside. Again, the sketch to the left shows a disconnectedstate, while the connected state is shown to the right. This embodimentcomprises a plug 510 with a hole through which the sterile optical fiberand ferrule 501, 502 can be inserted from one end. At the opposite endof the plug 510, a thin transparent membrane 507 is present, similar tothe one in the embodiment of FIG. 2. The plug 510 is shaped to fit intoa receiving body 505 into which the second ferrule 503 fits from theopposite side.

This embodiment is advantageous, since not only the membrane 507 createsa sterility barrier, but also the plug 510 serves to shield the sterileoptical fiber 502 from the receiving body 505. Therefore, the receivingbody 505 does not have to be sterile, hereby potentially saving costs.Potentially, a sterile sleeve could be attached to the plug 510 and bedraped over the receiving body 505 to shield the whole receiving body505 from the sterile zone.

FIG. 6 shows side view sketches of yet another embodiment for connectingfirst and second ferrules 601, 603, with respective optical fibers 602,604 arranged inside. Again, the sketch to the left shows a disconnectedstate, while the connected state is shown to the right. This can be seenas a further refinement on the embodiment of FIG. 5, in that thisembodiment comprises a plug 610 with a hole through which the sterileoptical fiber and ferrule 601, 602 can be inserted from one end. At theopposite end of the plug 610, a thin transparent membrane 607 ispresent, similar to the one in the embodiment of FIG. 2. The plug 610 isshaped to fit into a receiving body 605 into which the second ferrule603 fits from the opposite side.

However, in this embodiment the hole in the plug 610 is larger, and asecondary plug 611 serves to receive the sterile optical fiber andferrule 601, 602 can be inserted from one end of a through-going hole inthe middle. The advantage of having a plug 611 in a plug 610 is that theoutside plug 610 can be inserted at the beginning and be kept thereduring the whole procedure. The secondary plug 611 can be inserted andremoved from the primary plug 610 without leaving the sterile zone. Thisarrangement allows easy loading of several different sterile opticalfibers sequentially in the same interconnect. Furthermore, it ispossible to have fluid inserts and outlets in the primary plug 610 toflush and clean the sterile optical fiber 602.

In general, possible materials for the optical element in the variousembodiments described are: fluorinated polymers, polyethylene, andlatex. For the embodiment with an optically transparent membrane, it maybe preferred to use a material with a refractive index of 1.2 to 1.6,e.g. 1.4 to 1.5, e.g. 1.44-1.48, such as close to 1.46, which is thetypical refractive index of the cores in optical fibers. Preferably, thematerial should be thin, strong, and transparent in the relevantwavelength range. For example the near infrared wavelength range, morespecifically in the wavelength range of 1530 -1565 nm.

The optical connector according to the invention is applicable withinmany applications, especially where a miniature and reversibleconnection for sterile environment is desirable. Especially, theapplication entails minimally invasive medical interventions, and theuse of instruments that have a (optical) transmission line or cablerunning outside a sterile zone.

FIG. 7 illustrates steps of a specific method embodiment for reversiblyconnecting a first and a second optical fiber. The method embodimentcomprises providing P_F1 a first ferrule with a first optical fiberarranged inside, and providing P_F2 a second ferrule with a secondoptical fiber arranged inside. Next step is to provide P_RA a receptaclearrangement with an optical element, and finally inserting I_F12_RA endparts of both of the first and second ferrules into the receptaclearrangement such that an optical connection is provided between thefirst and second optical fibers via the optical element, wherein theoptical element serves as a sterility barrier between the first andsecond optical fibers.

To sum up, the invention provides an optical connector system forreversible optical connection between two optical fibers 102, 104 withtheir end parts inside respective ferrules. A receptacle arrangement hasa receiving body 105 for receiving at least one of the ferrules 103. Anoptical element 106 of the receptacle arrangement serves to provideoptical connection between the two optical fibers in a connected stateof the optical connector system, and at the same time, the opticalelement 106 serves as a sterility barrier between the two opticalfibers. The optical element 106 can be an optical waveguide, e.g. apiece of optical fiber similar to the two optical fibers 102, 104, andarranged within the receiving body 105. Alternatively, the opticalelement may be a thin flexible membrane 207, 307 which is opticallytransparent. As a further alternative, the optical element may be asterilizing fluid 409 arranged in side a container that can be puncturedupon insertion of one of the ferrules 401, 403 into the container 408,to allow an optical fiber end to be sterilized by the fluid 409 prior toentering into the connected state. In a further embodiment, an opticallens 312 is used to project light from one fiber end through a membrane307 to the opposite fiber end.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, such illustration and descriptionare to be considered illustrative or exemplary and not restrictive; theinvention is not limited to the disclosed embodiments. Other variationsto the disclosed embodiments can be understood and effected by thoseskilled in the art in practicing the claimed invention, from a study ofthe drawings, the disclosure, and the appended claims. In the claims,the word “comprising” does not exclude other elements or steps, and theindefinite article “a” or “an” does not exclude a plurality. Anyreference signs in the claims should not be construed as limiting thescope.

1. A medical optical system, comprising: an optical connector systemarranged to provide a reversible optical connection between associatedfirst and second optical fibers, each comprising multiple fiber cores,the optical connector system comprising: a first ferrule with an outerbody and arranged for having an end portion of the associated firstoptical fiber arranged inside, a second ferrule with an outer body andarranged for having an end portion of the associated second opticalfiber arranged inside, a receptacle arrangement comprising a receivingbody, wherein the receptacle arrangement is arranged to receive an endpart of the outer body of at least the second ferrule, wherein thereceptacle arrangement further comprises an optical element serving toprovide an optical connection between the associated first and secondoptical fibers in a connected state of the optical connector system, andwherein the optical element serves as a sterility barrier between theassociated first and second optical fibers, the optical connector systembeing configured for rotational alignment of the first and secondoptical fibers in the connected state of the connector system whereinthe optical element provides connection between each single fiber coreof the first and second optical fibers, and a rotational lockingarrangement preventing relative rotation between the first and secondferrules.
 2. Medical optical system according to claim 1, wherein thereceptacle arrangement is arranged to receive the end part of the outerbody of the first ferrule in one end, and to receive an end part of theouter body of the second ferrule in its opposite end, and wherein theoptical element comprises an optical waveguide arranged within thereceiving body.
 3. Medical optical system according to claim 1, whereinthe optical element comprises an optically transparent membrane. 4.Medical optical system according to claim 3, wherein the opticallytransparent membrane is flexible, and arranged to partially encapsulatethe associated first or second optical fiber in the connected state. 5.Medical optical system according claim 3, comprising a plug arranged toreceive the first ferrule, and wherein the plug is arranged to fitinside the receiving body.
 6. Medical optical system according to claim3, comprising a first plug arranged to fit inside the receiving body,and a second plug arranged to receive the first ferrule and to fitinside the first plug.
 7. Medical optical system according to claim 3,comprising a second optical element arranged to project light from oneof the associated first and second optical fibers via the opticallytransparent membrane to the opposite one of the associated first andsecond optical fiber.
 8. Medical optical system according to claim 1,wherein the receptable arrangement comprises a container with asterilizing fluid.
 9. Medical optical system according to claim 8,wherein said container is arranged to receive the first ferrule and topuncture upon insertion of the first ferrule into the container, so asto allow sterilization of at least an end part of the associated firstoptical fiber by means of contact with the sterilizing fluid, uponinsertion of the first ferrule into the container.
 10. Medical opticalsystem according to claim 8, comprising a sponge element within thecontainer, wherein at least a part of said sterilizing fluid is soakedinto the sponge element, and wherein the sponge element is arranged tomechanically clean at least part of the associated first optical fiberduring insertion of the first ferrule into the container.
 11. Medicaloptical system according to claim 10, wherein the sponge element has aprefabricated hole arranged for the first ferrule to penetrate through,so as to allow the associated first optical fiber to provide opticalconnection with the associated second optical fiber, in the connectedstate.
 12. Medical optical system according to claim 1, wherein thereceiving body is arranged to surround end parts of outer bodies of bothof the first and second ferrules in a connected state of the opticalconnector system.
 13. Medical system comprising an interventionalmedical device optically connected to an optical system, wherein theoptical system comprises: first and second optical fibers, eachcomprising multiple fiber cores, and an optical connector systemarranged to provide a reversible optical connection between said firstand second optical fibers, the optical connector system comprising: afirst ferrule with an outer body and an end portion of the first opticalfiber arranged inside, a second ferrule with an outer body and an endportion of the second optical fiber arranged inside, a receptaclearrangement comprising a receiving body, wherein the receptaclearrangement is arranged to receive an end part of the outer body of atleast the second ferrule, wherein the receptacle arrangement furthercomprises an optical element serving to provide optical connectionbetween the associated first and second optical fibers in a connectedstate of the optical connector system, and wherein the optical elementserves as a sterility barrier between the associated first and secondoptical fibers, the optical connector system being configured forrotational alignment of the first and second optical fibers in theconnected state of the connector system wherein the optical elementprovides connection between each single fiber core of the first andsecond optical fibers, and a rotational locking arrangement preventingrelative rotation between the first and second ferrules.
 14. A methodfor reversibly connecting first and second optical fibers, eachcomprising multiple fiber cores of a medical optical system, the methodcomprising: providing (P_F1) a first ferrule with an outer body and anend portion of the first optical fiber arranged inside, providing (P_F2)a second ferrule with an outer body and an end portion of the secondoptical fiber arranged inside, and providing (P_RA) a receptaclearrangement comprising an optical element, inserting (I_F12_RA) at leastand end part of the outer body of the first ferrule into the receptaclearrangement, so at to provide optical connection between the first andsecond optical fibers via the optical element, wherein the opticalelement provides connection between each single fiber core of the firstand second optical fibers wherein the optical element serves as asterility barrier between the first and second optical fibers, andwherein the optical connector system is configured for rotationalalignment of the first and second optical fibers in the connected stateof the connector system, and providing a rotational locking arrangementpreventing relative rotation between the first and second ferrules.